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To assess the prevalence and the incidence of hepatitis C virus (HCV) in a dialysis unit, we prospectively tested for anti-HCV in chronic hemodialysis patients and staff members since January 1989, using a first generation assay. Incidence was nil in staff and low in patients (3.7% in 89, 1% in 90), and prevalence was 30% in patients. In January 1991 blood samples from 115 patients were tested by first (EL1) and second generation (EL2) ELISA (Ortho Diagnostic System). Positive subjects were tested by a RIBA-2 confirmation test. Fifty-three patients were negative by all tests. Positive tests were observed in 62 patients (54%) including 36 positive in EL1 and EL2, and 26 only by EL2. All positive patients were reactive by RIBA-2 but nine were classified undetermined (only one positive band). In five patients reactivity of antibodies to 5-1-1 and C-100-3 gradually declined during the study. Second generation tests gave a better correlation with time on dialysis and blood transfusion. We conclude that second generation tests for HCV are more accurate for estimating true prevalence of HCV infection in hemodialysis units.

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The role of aluminum accumulation in articular tissues of patients affected by dialysis-associated arthropathy (DAA) is questioned. The aim of this work is to identify the nature of these aluminum accumulations by the use of secondary ion mass spectrometry (SIMS). Al/Si ratios of about 1, measured by SIMS, strongly suggest for the first time the presence of aluminum silicates and possibly aluminum hydroxides in amyloid synovial tissue and articular cartilage of 1 patient with DAA and aluminum intoxication. This is thermodynamically consistent with the total dissolved Al and Si contents and pH measured in the synovial fluids. These results are similar to the abnormal Al distribution recently found by SIMS in the forebrain of chronic renal dialysis patients and to the amorphous aluminum silicates identified in the core of senile plaques in Alzheimer's disease.

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The generation of compounds such as interleukin 1 (IL-1), tumor necrosis factor alpha (TNF alpha), and the possible encounter of circulating cells with endotoxin (LPS) have been demonstrated during hemodialysis. All these factors are able to induce the production of IL-6 by human monocytes. Anaphylatoxins can be generated following complement activation by cellulosic membrane dialysis. C5a is known to potentiate the LPS-induced production of IL-1 and TNF alpha, and we established that recombinant human C5a was able to act synergistically with LPS in the induction of IL-6 by human monocytes. We investigated whether IL-6 could be detected in the serum of long-term hemodialyzed and uremic patients. Using the very sensitive 7TD1 cell line bioassay, we demonstrated that circulating IL-6 activity was present in the serum of all 14 tested patients, whereas it was occasionally present in normal sera. The presence of serum IL-6 was confirmed using an anti-IL-6 antibody and a specific ELISA (109 +/- 36 pg/ml). Most patients had a reproducible level of IL-6 activity throughout a period of 10 days. The dialysis session did not significantly modify these levels and patients had similar serum IL-6 activity at the start, during or the at end of the dialysis session. The different parameters of the dialysis session (i.e. standard or filtrated dialyzates, complement-activating or nonactivating membranes) did not significantly influence the levels of IL-6. Elevated levels of IL-6 were also observed in uremic patients compared to normal donors, although significantly lower than in hemodialyzed patients (p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

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The phosphate kinetics during bicarbonate dialysis (BCD) and Acetate-free Biofiltration (AFB) were determined in 3 stable regular dialysis patients. These patients were switched to a 6-month period of AFB after a 12-month period of BCD. The plasma levels of phosphate, urea, and bicarbonate, and mass removal of phosphate and urea were measured every hour, during 3 consecutive dialysis sessions on BCD and AFB. The plasma phosphate behavior revealed a peculiar form with two main components, which differed from that of urea. The plasma phosphate level fell sharply during the first 2 hours of treatment, and then remained at a plateau towards to the end of the session. The plasma bicarbonate levels during the treatment sessions in the case of AFB were significantly higher than that in BCD. The actual mass removal in AFB was similar to that BCD, despite a significantly lower value of pre-plasma phosphate. A high ultrafiltration rate and better control of acidosis might be the reason for the better performance of phosphate mass removal in AFB. Better control of phosphatemia due to AFB can lead to a reduction in the amount of phosphate binders which have several untoward side effects.

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A systematic study of the upper cervical spine was performed using magnetic resonance imaging in 25 patients (15 men and 10 women) who had been undergoing hemodialysis for more than 10 years. Seven pseudotumors of the periodontoid soft tissue were disclosed, which were similar to the pannus recently described in rheumatoid arthritis. Bone cystic radiolucencies were observed in association with these pseudotumors in 5 patients. The radiolucencies were located in the atlas (1 in the lateral mass and 1 in the anterior branch) and in the axis (3 in the odontoid process and 1 in the vertebral body). No horizontal or vertical atlantoaxial subluxation was demonstrated. These features were observed only in patients who had amyloid arthropathy. They could be a frequent, yet thus far little-recognized, feature of beta 2-microglobulin amyloidosis.

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Adverse reactions, such as skin flush and pruritus, have been observed among hemodialyzed (HD) patients. A potential relationship between hemodialysis and allergic phenomena prompted us to investigate some allergologic parameters. Total IgE, specific IgE antiethylene oxide and anti-isocyanate toluene diisocyanate, and in vitro spontaneous histamine release (SHR) were measured in 105 long-term stable HD patients. Thirty-two of the patients had occasionally developed skin flush reactions and/or pruritus during dialysis sessions. Blood samples were taken at the start of dialysis, sera were kept frozen until assay, and in vitro SHR was performed on washed leukocytes at 37 degrees C for 40 minutes. A high (range, 20% to 80%) and reproducible in vitro SHR was observed among 24% of patients. No correlation was found between SHR and the type of dialysis membrane used (copolymer of acrylonitrile-methallyl-sodium sulfonate, cuprophan, and polysulfone). High SHR (i.e., greater than 20%) was observed mainly among patients with detectable antiethylene oxide IgE antibodies (p less than 0.001). High levels of IgE (greater than 300 ng/ml), specific IgE antibodies, and a high in vitro SHR were all observed concomitantly in 26% of the patients with skin flush reactions and/or pruritus, whereas all three of these parameters together were present in only 3% of the symptom-free patients. To our knowledge, this is the first time that a high in vitro SHR has been described among HD patients, and putative correlations with in vivo phenomena are discussed.

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The authors report the clinical history of a seventeen years old boy with renal failure treated with chronic haemodialysis since eleven and a half years of age. Growth velocity was 1.5 cm/year. The stature was below 5 SD as compared to the mean for the age. Hormonal measurements showed a complete growth hormone (hGH) deficiency and hyperparathyroidism. Thyroid, adrenal and gonadic secretions were normal, but the responses of TSH and prolactin to TRH were abnormal, showing an hypothalamic disturbance. hGH treatment, with thyroxin substitution, enhanced growth velocity up to 4 cm/year. Respective influences of hGH treatment, puberty and hyperparathyroidism on the incomplete correction of growth velocity are discussed.

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Pruritus is frequently observed in hemodialyzed patients; its etiology seems to be multifactorial. Increased plasma histamine levels have been reported in chronic renal failure. As histamine is a potent inducer of pruritus. The authors investigated its concentrations and kinetics in plasma of stable hemodialyzed patients.

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In vivo induction of interleukin-1 (IL-1) production during hemodialysis was investigated by measuring IL-1 activity in monocyte lysates from 59 patients undergoing long-term maintenance hemodialysis with complement activating and non-complement activating devices. In patients dialyzed with new hollow-fiber cuprophane dialyzers, predialytic (T0) monocyte-associated IL-1 activity was 12.5 +/- 3.0 U/ml (mean +/- SEM), a value that was higher than that found in normal individuals (2.85 +/- 0.85 U/ml; P less than 0.0025) and in non-dialyzed patients with chronic renal failure (0.95 +/- 0.85 U/ml, P less than 0.0001). Cell-associated IL-1 activity was consistently increased after five hours of dialysis with cuprophane membranes (42.4 +/- 5.5 U/ml, P less than 0.0005). Systemic complement activation was demonstrated by the finding of increased plasma levels of C3adesArg antigen during dialysis. In patients dialyzed with high permeability polyacrylonitrile and polysulfone membranes, no intradialytic change in cell-associated IL-1 and no complement activation occurred. However, the mean predialytic values of monocyte-associated IL-1 in these patients (that is, 32.9 +/- 5.6 U/ml and 38 +/- 5.65 U/ml for the polyacrylonitrile and the polysulfone groups, respectively) were higher than the predialytic levels of cell-associated IL-1 in the patients from the cuprophane group (P less than 0.0025). Monocytes obtained at the beginning and five hours of dialysis from patients dialyzed with polyacrylonitrile devices, and monocytes obtained at five hours but not at the beginning of dialysis from patients dialyzed with cuprophane membranes, spontaneously released extracellular IL-1 after 24 hours of culture in serum free conditions.(ABSTRACT TRUNCATED AT 250 WORDS)

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Administration of recombinant erythropoietin constitutes a revolution in treatment of the anemia of chronic dialysis patients. Such treatment has been anxiously awaited. Its realization has been possible thanks to the spectacular progress allowed by the newly developed techniques of recombinant genetics. Correction of this type of anemia can be obtained rapidly and permanently if treatment is continued without interruption. It is followed by a remarkable transformation of the patient's physical and psychic status. The occurrence of certain side effects (e.g., elevation of blood pressure and an increased tendency toward vascular thrombosis), however, requires increased awareness in the follow-up of patients at risk and adaptation of erythropoietin administration to individual needs.

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The hormones regulating growth, growth hormone (hGH), IGF I, sex steroids, thyroxin (T4) and parathormone (PTH) have been measured in 23 adolescents aged from 13.5 to 20 years (14 boys, 9 girls), with chronic renal failure treated with haemodialysis. Growth velocity (GV) was (mean +/- DS) 4 +/- 2.1 cm/year in boys and 1.6 +/- 1.65 in girls, with a bone age of 12.9 +/- 2.4 cm/year. T4 and DHA sulfate (DHAS) differed according to sex (boys: T4 = 70 +/- 4.7 ng/ml; DHAS = 655 +/- 139 ng/ml; girls: T4 = 102 +/- 16.6 ng/ml; DHAS = 118 +/- 35 ng/ml). IGF I, within normal limits, was correlated to bone age and pubertal stage. T4 was negatively correlated to testosterone and SDHA in boys. GV expressed as SD according to bone age was negatively correlated to PTH.hGH deficiency was evidenced in one case, and GV increased under hHG therapy. It is concluded that measuring hormones is necessary in renal failure. Secondary hyperparathyroidism is an inhibiting growth factor. Possible hormonal deficiencies have to be treated.

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A retrospective study of 40 patients with chronic renal failure who underwent haemodialysis for more than 10 years (mean: 153 months) showed that 18 patients (45 p. 100) had arthralgia in the shoulders, hands, wrists and knees, 13 (32 p. 100) had carpal tunnel syndrome requiring surgery, and 20 (50 p. 100) were found to have bone cavities in the humeral head, external supra-acetabular region, carpus and patella. Aluminium overload was present in 47 p. 100 of the patients, and amyloid deposits were found in 10 of the 12 patient operated upon for carpal tunnel syndrome. This study confirms the frequency in patients under long-term haemodialysis of an articular pathological entity consisting of arthralgia, carpal tunnel syndrome, juxta-articular bone cavities and amyloid deposits which are now known to be made of beta 2-microglobulin. The initial lesion seems to affect the synovial membrane; it appears to be facilitated by age and is often associated with aluminium overload. The mechanism(s) responsible for amyloid deposits remain (s) to be elucidated.

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